|
| Season and crop species | Cultivation method | Straw application method | Cumulative number of straw applications (CNSA) |
|
| Winter-seeded rape plant in 2016 | Sowed on 10-25-2016. Mechanical furrowing was conducted at a depth of 8−12 cm. Then, a thin layer of soil was applied. Thinning was conducted at V2 and final thinning at V4 during intertillage and weeding. Fertilizers were applied at 276 kg/ha for N, 120 kg/ha for P2O5, and 150 kg/ha for K2O. Nitrogen fertilizer was given at sowing, germination, and inflorescence emergence at a ratio of 3 : 3:4. Phosphorus and potassium fertilizers were applied at sowing. Top dressings were applied to the furrows between two rows. Crop maintenance was conducted according to the standard practice for high-yield crops. | Mechanical grain harvesting was carried out, and straw was shredded on 4-20-2017. SDBP: straw was buried at 30−40 cm during plowing. Then, rotary tillage was carried out. SSBRT: straw was buried at 15−20 cm during rotary tillage. SMMT: straw was directly applied to the surface of the soil. | Cumulative zero rounds of straw application before the rape plant was sown in 2016 (0 CNSA) |
| Summer-seeded maize in 2017 | Sowed on 4-28-2017 at a density of 67,500 plants/ha. Mechanical furrowing was conducted at a depth of 10−15 cm. The fertilizer was applied at 180 kg/ha for N, 112.5 kg/ha for P2O5, and 135 kg/ha for K2O. Nitrogen and potassium fertilizers were given at sowing and inflorescence emergence at a ratio of 5 : 5. Phosphorus fertilizer was applied at sowing. Fertilizers applied during the period of inflorescence emergence were applied into furrows, and top dressings were applied into deep holes punched between every two crops. Crop maintenance was conducted according to the standard practice for high-yield crops, and each plot was treated the same. | Mechanical grain harvesting was carried out, and straw was shredded on 10-15-2017. Straw application was carried out as per the three methods of the winter-seeded rape plant in 2016. | Cumulative one round of straw application before maize was sown in 2017 (1 CNSA) |
| Winter-seeded rape plant in 2017 | Sowed on 10-28-2017. The same method as winter-seeded rape plant in 2016. | Mechanical grain harvesting was carried out, and straw was shredded on 4-25-2018. Straw application was carried out as per the three methods of winter-seeded rape plant in 2016. | Cumulative two rounds of straw application before the rape plant was sown in 2017 (2 CNSA) |
| Summer-seeded maize in 2018 | Sowed on 5-1-2018. The same method as summer-seeded maize in 2017. | Mechanical grain harvesting was carried out on 10-22-2018. | Cumulative three rounds of straw application before maize was sown in 2018 (3 CNSA) |
|
